Manchester United goalkeeper Joel Pereira dropped a howler for loan club Hearts last night.
Pereira apologised to his Hearts teammates on Wednesday night after they lost to Kilmarnock in the Scottish Premiership.
“Should he have done better? Yes," Stendel said about Pereira's mistake. “He apologised in the changing room, but it was not his fault that we lost the game.
“We know that he can save that shot - but as a team we must do better in a lot of situations. Situations like that can happen. It is disappointing we came from half-time with motivation and conceded a goal like that.
"It is hard for me to explain what happened. To concede three goals against Kilmarnock is not what we expected. It was a crazy game. It was not the way we can play or the way we want to play."
Pereira has played 23 times in all competitions for Hearts this season, keeping just four clean sheets and conceding 38 goals. Six of those have come in the past two games with Hearts conceding three in each.